Alarm means



G. D. PEASE Jari. 13, 1942.

ALARM MEANS Filed April 7, 1959 INVENTOR. Z0/(96E Q PESE BY w, em, 67 ATTO l RNEY Patented Jan. 13, 1942 UNITED `S'TBi'I'E S "PAT EN T OF FICE 2,270,226 ALARM MEA-Ns "Georgezil Tease, Cedar apda Iowa iAlmirante Afpriiv, 1939, serial No. 266,516

4 claims. (on. nea-rot) u 'This invention relates "generally to signalling devices and 'in'particul'ar :to an excess temperaturealar'm rd'evi'ce.

, It is a .general object of my invention to provide a sel-f contained cartridge type of alarm device for attracting attention when the vtempera.- fture at the location ofthe alarm reaches a predetermined danger point.

It is another object of my invention to provide such a device as will indicate lthe general location of such `excess temperatureor danger point.

It is a further lobject of my invention to provide a device of this vcharacter which may be handled and shipped with complete safety.

It is a still further object of my invention to provide a devicefthat is V"simple in construction 4and inexpensive to manufacture and maintain.

An additional `object of my invention is to pro- `vide a vsignalling device 'in Va icartridge `form, so

constructed 'as to Vbe tamper-proof `and so low in cost that such cartridges may be discarded after `lfiaving fullled their purpose.

, Other and further features and obj'e'cts o'f the uinvention will be more apparent fto those skilled in the art upon a consideration of the` accompanying drawing and `following specification, wherein are ldisclosed several exemplary embodiments of the invention, with the understanding, however, lthat such changes may be made therein as 'fall within the scope of the appended claims, without departing from the spirit of the invention.

In said drawing:

Figure 1 illustrates, in perspective, a cartridge type excess temperature signalling device constructed in accordance with one embodiment rof my invention.

, Figure `2` illustrates, in section, the construction` of the device shown "in `ligure 1.

Figure 3, is a modi'ed form of the structure shown in Figure 2.

Figure 4 is :a sectional View of a tamper-proof type of cartridge as constructed in accordance with another modification of my invention, and Figure 5 is a view in perspective, in enlarged relation, of the safety device and fusible plug ofthe device `shown in Figure 4. n

Figure 6 is aview in section of a .modified means for supporting the shell-within the end of the' cartridge.

Figure f7 is an enlarged View of vthe tapered opening in the. end of the device shown in Figure 4. y

Referring now more particularly vto Figures 1 and 2, one embodiment of my invention includes in 'general `a cartridge type of structure having a barrel indicated generally at 'ID adapted to hold, at one end, a bla-nk cartridge such as a blank shotgun shell or the like, as indicated at `ITI. 'At detonator pin I2 within the barrel and 'extending lengthwise thereof is biased strongly Vin the direction ofthe detonatorca'p of the shell by springmeans, Vindicated generally at I3.

In the device shown the barrel I0` may be of anysuitabi'e materialsuch as metal or fiber hav- 'ving a rim insert or ange member I4 inset in one end thereof to snugly receive the shell or blank 1cartridge II. The opposite end of the barrel I0 maybe threaded, as at I6, to removably receive a'c'ap il.

The `detonator pin I2 may be cylindrical in `form if desired, but is preferably `flat at the 'por- 'tion [2a which Jextends through an opening `I'Ia in the cap.` VThe flattened portion of the pin is 'provided with two openings, one at I8 through whicha fusible key I9 is inserted to h'old the det- "onatcr pin-ready to re. This key may be made of? any 'fusible alloy with a 10W melting point suitabie' ifo'r the purpose intended. Fusible alloys `metal maybe used when a very low temperature alarm is desired.

The compression spring I3 is positioned within the barr'el with one end bearing against the cap I'I and the other end bearing against the washer or 'cup-shaped member 2`I which is retained on the `detona'tor vpin near the inner end by means such as a pin 22.

It is preferable that the end of the detonator pin be made conical rin shape to provide a small 'contacting area Izb.

The barrel may be provided with a strap membei such as indicated at 23 to permit supporting the` device in the desired location. The strap 'member may 'be spot welded or otherwise fastened, as at 2li, to the barrel and may be provided with openings 2li through which nails or screws may be inserted.

ces may be used for fire protection vfor buildings. 1t is preferable that they be located at Yscattered points 'around the building. Since heated air rises, it is of course apparent that they will serve their purpose best if they are lodatfed at the high `points in a building, such `as inthe peak of a roof or above any combustible materials, or near the ceiling in basements Where cembustible materials are stored.

, In operation, the presence of heat in excess of the melting point of the key member I9 serves It is apparent that one or a plurality ofthese to melt that member, permitting the spring to snap the detonator pin against the detonator cap of the blank cartridge This cartridge may be filled with regular powder or may be filled with a mixture of regular powder and magnesium powder or the like to provide a bright flash as well as an explosion to locate the danger point. The cartridge may of course be provided with a slower burning illuminating means such as magnesium ribbon or the like to cause a flare rather than a flash of light.

A shield 25 may, if desired, be formed of light gauge metal with a plurality of slits or perforations 25a for prevention of injury to nearby persons. The shield may be slipped on the end of the body I and held in place by welding, pins or other means.

The iiat portion of the detonator pin is provided with another opening |917 through which a pin or cotter key |9c may be installed while handling and during shipping to prevent premature explosions.

I preferably provide a felt or other type of insulating washer as shown at 20 to minimize the conduction of heat away from the fusible key. This permits the rapid response of the safety device to temperature changes. The small body of the key absorbs radiant heat quickly as compared to the large body of the barrel.

The threaded cap permits the recharging the device with a fresh cartridge and with a new fusible key.

The modied form of my invention illustrated in Figure 3 utilizes a firing pin which may be stamped from a flat sheet of metal rather than built up of a rod and washers and like materials. This modified form of the detonator pin, as indicated generally at 30, includes a portion 3| of a size to loosely lit in the opening |1a in the cap. This portion may be enlarged as at 32 to form the main body of the pin enclosed within the spring I3. Hook-shaped projections 33 extend beyond the body portion 32 so as to receive the end of the spring in place of the washer shown at 2| in Figure 2. The end of the pin is tapered down to a firing point 34. Openings 36 and 31 are provided in the same manner as the embodiment shown in Figure 2 for the reception of the fusible key member 38 and a Cotter key or other safety locking device.

The embodiment of my invention illustrated in Figure 4 is directed particularly to a throwaway type of cartridge constructed so as to be tamper-proof. The main barrel of the device may be constructed of a light tubular material such as indicated at 4|, formed or flared inwardly as indicated at 42 to form a restricted or tapered opening 43 through which the deton'ator pin 44 extends. The washer means 46 may be retained on the firing pin in any suitable manner as by a locking washer 41 snapped on a recessed portion 48 of the pin.

The firing pin may be held in the cocked position by means of a small block 49 of fusible metal keyed into the shaft as at and adapted to jam within the restricted opening of the barrel at 43. It is apparent that melting of this plug will release the firing pin. The lower end of the barrel, as at 52, may be received within and fastened by means such as welding, within a short lower barrel 53. A plug member 54 is received within this lower barrel and adapted t0 rest against the lower end of the barrel 4|. An opening 56, extending through the plug which may be of metal or any other suitable material,

serves as a guide for the firing pin. The detonator cap of the shell is aligned with the outer end of the opening 56, the shell being supported in position by means of a collar 51 which ts snugly over the cartridge and within the lower barrel 53. The outermost end of the barrel is rolled over this collar, as indicated at 58, to hold all parts in their proper position and to seal the device against tampering.

The outer end of the firing pin may be provided witn an opening as before described for the insertion of a pin safety means. It is preferable, however, that the tamper-proof type of cartridge be provided with a safety means such as indicated generally at and as more fully disclosed in Figure 5'. In this construction the outermost end of the shaft at a point close to the fusible plug is flattened to provide an enlarged section 6| to prevent its passing through the constricted opening 43 in the end of the barrel. This prevents the :tiring pin from being accidentally released during shipping or installation. Slots are provided on either side of the pin just within the enlarged portion, as indicated at 62, leaving only a thin sectionA 63 which may be snapped in two with a pair of pliers after installation. The removal of this safety head helps to eliminate tampering and attempts to refill the cartridge.

I have shown in Figure 6 a means for clamping the explosive shell within the end of the cartridge construction shown in Figure 4. The shell 4| is rolled or beaded inwardly as at B5 to form a shoulder. After the shell is in place the end of the shell 4| is rolled over the shoulder of the shell, as at 61, to hold it in place and eliminate the collar members 54 and 51 and in fact eliminate the necessity for the lower barrel 53.

It is apparent that I have provided a device for the indication of dangerous temperatures and one which may be adapted to a Wide variety of uses, which is simple and positive in action, and which may `be constructed very inexpensively. The light from successively exploding alarm devices will guide remen to the fire source.

I have further devised a structure of a type that will discourage tampering and attempts at refilling after having once been used.

Although I have described specific embodiments of my invention, it is apparent that modifications thereof may be made by those skilled in the art. Such modifications may be made without departing from the spirit and scope of my invention as set forth in the appended claims.

I claim as my invention:

l. In a device of the type described and having a barrel with a restricted opening through the end thereof, a firing pin extending through the opening and fusible means for releasing the firing pin at a predetermined temperature, a safety means on the iiring pin to prevent premature explosion comprising a flat and enlarged portion on the outermost end of the firing pin to prevent the said outermost end from passing through the opening, and cut-away portions in the sides of the pin adjacent to the enlarged portion so that the enlarged portion can be snapped olf after installation of the device.

2. In a device of the class described, a tubular shell closed at one end and open at the other,

.means for holding a cartridge in the open end, a

plunger extending through the closed end, means for guiding the plunger within the tubular shell, means for biasing the plunger toward the cartridge to fire it, the plunger having a recess therein positioned so it is outside the shell when the plunger is retracted, and low melting point alloy metal located within the recess for bearing against the outside of the closed end for holding the plunger in retracted position against the biasing effect of the spring until an ambient temperature is reached at which the metal melts to permit the plunger to be driven against the cartridge, and the outer end of the plunger being attened whereby the flattened end prevents the plunger from striking the cartridge as long as the flattened end is present, the plunger -being partially cut away near the attened end to permit the iiattened end to be broken away to render the device operative when it has been installed.

3. In a cartridge type excess-temperature alarm, a tubular shell formed at one end to provide an inwardly tapering opening, means at the other end of the barrel for non-removably supporting in iixed vposition an explosive cartridge, a detonator pin contacting the detonator cap of the explosive cartridge, when released, and extending through the tapering opening first mentioned, a coil spring under compression, one end of same bearing against the inner surface of the barrel at the end thereof lirst mentioned, the other end of the spring engaging the detonator pin, and means for holding the detonator pin in cocked position comprising a block of fusible metal keyed into the side of the detonator pin and jamming within the tapering opening in the barrel.

4. In a cartridge type, excess temperature alarm device, a tubular barrel, means comprising a rim rolled on the end of the barrel for supporting an explosive cartridge, the base of the cartridge resting inside the barrel and against the rim, other means bearing against the flat portion of the base of the cartridge to prevent movementthereof longitudinally of the barrel, a detonator pin within the barrel, means for guiding the end of the detonator Ipin adjacent the base of the cartridge, spring means within the barrel for biasing the detonator pin toward the cartridge, the barrel being constricted at the end opposite the cartridge to engage the adjacent end of the spring means and to closely receive the detonator pin, the Wall ofthe opening, thus formed, tapering inwardly toward the detonator pin, and a plug of a fusible alloy secured to the detonator pin at a point outside the barrel whereby the spring means will jam the fusible plug in the tapered opening and whereby the possibility of the fusible plug becoming accidentally sheared off through jarring is greatly lessened.

GEORGE D. PEASE. 

